Getting Access Denied when calling the PutObject operation with bucket-level permission

Question

I followed the example on http://docs.aws.amazon.com/IAM/latest/UserGuide/access_policies_examples.html#iam-policy-example-s3 for how to grant a user access to just one buck

Answer 1

I was just banging my head against a wall just trying to get S3 uploads to work with large files. Initially my error was:

An error occurred (AccessDenied) when calling the CreateMultipartUpload operation: Access Denied

Then I tried copying a smaller file and got:

An error occurred (AccessDenied) when calling the PutObject operation: Access Denied

I could list objects fine but I couldn't do anything else even though I had s3:* permissions in my Role policy. I ended up reworking the policy to this:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "s3:PutObject",
                "s3:GetObject",
                "s3:DeleteObject"
            ],
            "Resource": "arn:aws:s3:::my-bucket/*"
        },
        {
            "Effect": "Allow",
            "Action": [
                "s3:ListBucketMultipartUploads",
                "s3:AbortMultipartUpload",
                "s3:ListMultipartUploadParts"
            ],
            "Resource": [
                "arn:aws:s3:::my-bucket",
                "arn:aws:s3:::my-bucket/*"
            ]
        },
        {
            "Effect": "Allow",
            "Action": "s3:ListBucket",
            "Resource": "*"
        }
    ]
}

Now I'm able to upload any file. Replace my-bucket with your bucket name. I hope this helps somebody else that's going thru this.